1. Technical Field
The present disclosure relates to a resin composition used as a material of a printed wiring board, a prepreg, a metal-clad laminated plate, a metal foil with resin, and a printed wiring board.
2. Description of the Related Art
In the related art, a technology of improving heat resistance by improving a glass transition temperature (Tg) or the like of a printed wiring board used in an electronic device has been achieved. Flame retardant properties of a printed wiring board have also been achieved. In recent years, particularly in the field of small-sized electronic devices such as mobile devices, it is required to further reduce a dielectric constant and a coefficient of thermal expansion (CTE) of a printed wiring board in the market, in order to realize a small size, a thin thickness, and multi functions of a device. In general, a resin composition containing an epoxy resin is used as an insulating material of a printed wiring board. In this resin composition, a phenol-based hardener, a diamine-based hardener, a cyanate-based hardener, an anhydride-based hardener, and the like are used as a hardener of the epoxy resin. Among these hardeners, it is known that the anhydride-based hardener is effective, in order to reduce a dielectric constant. As the anhydride-based hardener used in the related art, an anhydride-based compound having a plurality of anhydride rings in one molecule or a styrene-maleic anhydride copolymer is used. The styrene-maleic anhydride copolymer can be expressed as a styrene-maleic anhydride copolymer. In addition, the styrene-maleic anhydride copolymer is also abbreviated as SMA. For example, Japanese Patent Unexamined Publication No. 9-194610 discloses a technology of using a copolymer having styrene and a maleic anhydride as compulsory components, as the anhydride-based hardener. This copolymer is the same as SMA.